Measuring rotary and angular motions, and, in particular, the speed and the rotational behavior of individual wheels on a vehicle is of great importance in connection with automotive vehicle control systems for anti-lock control brake systems (hereinafter ABS), traction slip control, and suspension control, etc. Sensors for these types of applications must be durable, reliable, inexpensive to manufacture, easy to assembly easy to diagnose, replace and maintain.
There are a number of sensor types and sensor designs that are available for detecting rotary and angular motion of vehicle wheels. For example, in some commercially available vehicles with electronically controlled anti-lock and traction slip control systems, an incremental encoder, which is coupled mechanically to the vehicle wheel, cooperates with a transducer or sensor to collect positioning data for the vehicle wheel.
In known applications, the sensor is connected to a bearing dust cap by clips, bolts or other known fasteners. These methods of attachment is undesirable as it increases the number of components for the bearing assembly, translating into increased costs. Further, packaging concerns arise as it is necessary to provide additional space within the dust cap to properly accommodate the fasteners necessary to secure the sensor. As a result, positioning space for accommodating the encoder is undesirably limited, such that substantial packaging constraints for the encoder arise. Accordingly, the diameter of the encoder must be limited to insure proper operation of the encoder.